Improvement in hot-air engines



UNITED STATES PATENT OFFICE.

HENRI J. KRITZER, OF ALBION, MICHIGAN.

IMPROVEMENT IN HOT-AIR ENGINES.

Specification forming part of Letters Patent No. 36,008, dated July 29,i862.

f tional view, and Eig. 3 a plan of condensingpiston.

This improvement consists mainly in charging with air and water underpressure aseries of hot and cold supply-cylinders arranged in pairs insuch manner that when the circulation is closed between them theexpanded air can be condensed by simply lifting a piston7 or plungerfrom the cold to the hot cylinder and so destroy the equilibrium ofpressure. Also, 1n interposing a body of water between theworking-piston of the engine proper and the condensing-pistons to servethe treble purpose of lubrication, packing, and also to act as a wellfrom which the ascending pistons can draw a supply of water to saturatethe hot dry l air and increase its elastic force, the several partsbeing arranged relatively in the manner I am now about to relate.

A is the frame, carrying a crank-shaft, B, working-cylinder O, and allthe usual appurtenances of an ordinary reciprocating engine, needing nospecial description excepting in regard to certain modification ofparts, to be v mentioned hereinafter.

Two cylinders (usually of castiron) open at the lower ends, and of areasabout two and a half times that of thefworkingcylinder, are connectedtogether by two branch pipes, a and l), and placed in a verticalposit-ion and parallel with the engine ou a bed-plate, G, towhich theyare securely bolted through the bottom flan ges. Each of these twocylinders are formed by two distinct sections, which are boltedtogether, as seen at E, a thick packing-ring, e, of some material whichis a good non-conductor of heat being interposed between the flanges.The upper section, D', I call the hot or generating7 cylinder, and thelower', D2, (which is much longer than the upper,) the cold orcondensing7 cylinder'.

The bed-plate G rests upon and is secured to a flat surface at each endand on the upper side of the cylinder C, making a close connection, andthe opposite side I generally secure by bolts passing through two hollowcolumns (not shown) erected on the frame.

J J are the condensing-pistons. They are tight hollow cylinders and of adiameter enough smaller than that of the stationary ones in which theywork to admit of being surrounded by a cylindrical shell, j, with spacebetween to allow the heated air from D to pass freely through. The outershell portion, j, of the piston acts as a regenerator in returning aportion of its absorbed heat, and I usually attach it to the shell ofthe piston by bolting with flush-headed bolts through narrow interveningstrips x x, as may be more clearly seen at Fig. 3.

L L are the "sprinkling-troughs," made of any light suitable metal. Thesides are perforated with small holes, and the whole constructed andattached in such manner to the bottom of the piston J that on eachdescent of said piston it will be filled with sufficient water from thelower part of the cylinder Dl to continue the shower withoutintermission.

To ease the shock on striking the water, I usually employ a disk-float,o, the center of which is cored out sufficiently'to admita spiralspring, s, which surrounds loosely the liftingrod M, and extends abovethe boss in such manner that the bottoni of the sprinkler will rststrike against the end of the spring before coming in contact with theboss of the disk.

The condensing-pistons J J are lifted alter nately by means of atriangularshaped cam, V, on the engine-shaft, which hooks by its rod toa rocking shaft, R, carrying two arms, (indicated by dotted lines,) theends of which are jointed to rods M M,that pass through stuff` ing-boxesin the bed-plate G. As the only duty of these liftingrods is to raisethe pistons J J, which are fitted quite loosely in the cylinders, itwill be readily seen that the actuating machinery can be made quitelight. Should it be found necessary to render the condensation moreperfect, I propose to surround the cylinders D2 with alight metal sheetattached to the edges of the flanges and keep the intervening spacefilled (from a tank) with cold water.

iiame circulates. Inside of these tubes I placeY others, V V V, whichrest on the tops of the pistons J J and slide np and down with them forthe purpose of multiplying the heatingsurfaee.

The inode of operation is as follows: The safety-valve being set to theworking-pressure and the gage cock c opened, Ipump in water through thebranch I to that level and then close the cock. The water, as will beseen by reference to Fig. 2, is driven upward through one of the ports Funt-il it reaches the branch b, provided with a stop cock, (previouslyopened,) when it descends through the other port F and lls the space onthe opposite side of the workingpiston p. The water-cock is now closedand airis pumped in by hand to the pairs of cylinders D D2 (the cock inthe pipe a being open) until the safety-valve lifts, when the aircock isclosed, and the weight on the valve-lever is moved ont to provide forthe additional pressure obtained by the eXpanison in heating.

I usually pump in air by the same pump as I do water, through astop-cock fitted to the lift; but a separate air-pump may be used toadvantage.

A fire being started in the furnace, the calnrod is unhooked, andthepistons J J are placed at half-stroke, which permits the air in thehot cylinders D D to be equally expanded. lIhe engine is now to be insuch position that when the safety-valve indicates suficie'nt pressureand the cam-rod is hooked in the pistons are suddenly displaced, oneascending to the top and the other descending to the bottom of itsstroke. The ascending piston now nearly fills the hot air cylinder andtrans fers its contents to the condensing cylinder below, which destroysthe equilibrium, throws the pressure on one side of the driving-pistonp, and puts itin motion. About the time the piston p has reached the endof its stroke, the relative positions of the condensing-pistons arereversed and the return-stroke made by the expansion and condensationconsequent to the change. As theWorking-pistonp moves back and forth thewater in the condensingcylinders must rise and fall accordingly. Now, asthe rods M M are not attached to the pistons J J, but merely abutagainst the bottoms, it

follows that when either of the pistons J J in its descent on its rodreaches the descending water, the rod (traveling much faster by theaction of the cam w than the Working-piston p) will be drawn away fromunder it and allow it to follow the motion of the water and graduallysink, so as to submerge the sprinklingtrough L, when it is caught anddetained by the spring or other similar device until the rod on itsupward stroke lifts it from the water with the sprinkler full. As thesprinkler L begins to discharge its contents in the interior of thecondensingcylinders, the temperature is inimediatelylowered and thecontained air charged with particles of water is drawn up into theheated cylinder D', when its susceptibility of increased expansion isdemonstrated by a rapid increase of motion immediately.

It is essential to the success of niy engine that vthecondensing-pistons shall move as rapidly as possible-1irst, to rest aslong as possible on the downstroke,` so that the air in the hot cylinderD may be exposed to the action of the iire; and, secondly, that when theupstroke is made a more perfect condensation can be effected beneath.

This engine is found to be cheap in construction and very durable, andto utilize its heat as well as others of its class.

I do not claim, broadly, expanding and condensing air in a singlecontinuous chamber, nor causing condensation by the movement of a pistonfrom acold portion of such chamber to another exposed to heat. Neitherdo I claim as new (independent of the peculiar mode of application) tnemixing of water with air to be heated, so as to render it moresusceptible of expansion; but

Vhat I claim, and desire to secure by Letters Patent, is-

1. The combined arrangement (substantially as described) of the pair ofconnected heating and condensing cylinders D' D?, condensingioat-pistons J J, lifting-rods M M, and water-ports F F, for'the purposeof interposing a body of cold water or other suitable Huid between thecondensing and working piston to lubricate the working parts,facilitate'condensation, and allow the air-chambers to be permanentlycharged without risk of loss by leakage.

2. The use o f the sprinkling-troughs L L, in combination With thearrangement aforesaid, substantiall y as and for the purposes specited.

HENRI J. KRITZER.

Witnesses:

GEORGE JoHNsoN, F. W. SHEARMAN.

